There is relatively high demand for microfluidic systems due to their needed small size, easy portability, and low cost for research, civil, and even some military applications. One core device of a microfluidic system is a micropump. In the past decades, researchers have proposed and developed various micromachining micropump prototypes. Commercially available micropumps made with batch fabrication techniques still under development and may be improved.
One example of a micropump includes a check valve diaphragm micropump. Due to the small stroke of the diaphragm and a comparatively large chamber volume, the diaphragm micropump usually has a relatively small compression ratio (i.e. the ratio of stroke volume to chamber volume). This makes it difficult for such a micropump to deliver gases that have a comparatively high compressibility. It is also difficult to transport liquid that contains air or gases, since the gas pockets accumulate in the chamber and have high compressibility.
For check valve diaphragm micropumps, rigid check valves and diaphragms are unsuitable, since the resistance of the valve is greater than the pressure difference created by the diaphragm actuation mechanism. However, overly flexible check valves and diaphragms are also unsuitable, since leakage would be high and the dynamic response of the micropump would be low, precluding an expected linear working range.
In view of the above, it is apparent that there exists a need for an improved micropump and method of producing micropumps.